Right now, the only 'trade-able' goods I can think of is staff, especially drivers. So my suggestion is this:
The trading of drivers, for reward points.
Right now, one team can only release a driver, not 'send it'. High level managers with a YDA could collect a bit more reward points this way, as lower level managers would get top talent drivers.
Ideally you'd have this possibility for in-game money too, not just reward points, but there would be no stopping managers from making satellite teams and selling lvl 1 drivers to rake in a lot of money.
In-game trading would make it feel more like an MMO, not just competing with eachother but also on a different level.
Inspiration: World of Warcraft auction house
